While upgrading from 5.5 to 5.6 I am getting this error (percona mysql

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1

I upgraded 5.5.40 to 5.6.21 percona mysql on slave.

But I am found the below errors and the version has been changed successfully

Native table ‘performance_schema’.‘events_waits_summary_by_user_by_event_name’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_waits_summary_by_account_by_event_name’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Column count of mysql.file_summary_by_event_name is wrong. Expected 23, found 5. Created with MySQL 50540, now running 50621. Please use mysql_upgrade to fix this error.
2014-12-26 05:18:20 13215 [ERROR] Column count of mysql.file_summary_by_instance is wrong. Expected 25, found 6. Created with MySQL 50540, now running 50621. Please use mysql_upgrade to fix this error.
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘host_cache’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Incorrect definition of table performance_schema.mutex_instances: expected column ‘LOCKED_BY_THREAD_ID’ at position 2 to have type bigint(20), found type int(11).
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘objects_summary_global_by_type’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Incorrect definition of table performance_schema.rwlock_instances: expected column ‘WRITE_LOCKED_BY_THREAD_ID’ at position 2 to have type bigint(20), found type int(11).
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘setup_actors’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘setup_objects’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘table_io_waits_summary_by_index_usage’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘table_io_waits_summary_by_table’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘table_lock_waits_summary_by_table’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Column count of mysql.threads is wrong. Expected 14, found 3. Created with MySQL 50540, now running 50621. Please use mysql_upgrade to fix this error.
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_stages_current’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_stages_history’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_stages_history_long’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_stages_summary_by_thread_by_event_name’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_stages_summary_by_account_by_event_name’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_stages_summary_by_user_by_event_name’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_stages_summary_by_host_by_event_name’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_stages_summary_global_by_event_name’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_statements_current’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_statements_history’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_statements_history_long’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_statements_summary_by_thread_by_event_name’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_statements_summary_by_account_by_event_name’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_statements_summary_by_user_by_event_name’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_statements_summary_by_host_by_event_name’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_statements_summary_global_by_event_name’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘events_statements_summary_by_digest’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘users’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘accounts’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘hosts’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘socket_instances’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘socket_summary_by_instance’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘socket_summary_by_event_name’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘session_connect_attrs’ has the wrong structure
2014-12-26 05:18:20 13215 [ERROR] Native table ‘performance_schema’.‘session_account_connect_attrs’ has the wrong structure
2014-12-26 05:18:20 13215 [Note] Event Scheduler: Loaded 0 events
2014-12-26 05:18:20 13215 [Note] /usr/local/mysql/bin/mysqld: ready for connections.
Version: ‘5.6.21-70.1-log’ socket: ‘/tmp/mysql.sock’ port: 3306 Percona Server (GPL), Release 70.1, Revision 698

2

Try running mysql_upgrade on the shell prompt and check your log file again. If you upgrade from one major version to another, in this case from 5.5 to 5.6 it is advised to run mysql_upgrade to check all tables on all databases for incompatibilities with the current version of MySQL server.